The Application Of Heat Pump Drying Technology In Fruit And Vegetable Drying

Fruits and vegetables after heat pump drying technology for dehydration can guarantee the features of fresh fruits and vegetables very well, More major is fresh fruits and vegetables drying after losing most of the water can reduce the occupied space with features and quality of fresh fruits and vegetables, due to the moisture content is very small, is not conducive to microbial growth, make shelf life growth,therefore, heat pump drying of fruit and vegetable products very accord with the market demand.In international fruit and vegetable drying market, heat pump drying technology in the production of dehydrated and dry products generally can reach the price of 2 times more than ordinary dehydrated and dry products,supply products far cannot satisfy the demand.The principle of heat pump drying equipment is a kind of inner loop off the water system of fruit and vegetable, relative to other drying methods, both can save energy consumption and protection of the environment as far as possible, more major is engaged in the industry of capital threshold is low, ordinary enterprises can be engaged in the processing of this kind of dry products.Therefore, heat pump drying is a kind of existing improvement on drying technology, can make the drying technology to conduct a comprehensive upgrade of existing, heat pump drying technology is widely used in fruit and vegetable drying has a very good economic benefits and profound social significance.This study choose 6 kinds of common fruits and vegetables, carrots, mushrooms, konjac,yam, apple and pineapple, including two research direction:First, respectively studied the selection of several kinds of fruit and vegetable respective parameters in the process of heat pump drying technology, get the parameters for the every fruit and vegetable, drying process in detail is as follows:(1)The carrots: fresh carrots-washed clean-take the edible part-cut into filaments(s ize of 4 mmx2mm)-heat pump drying(40?,8h,drying quantity is3kg/m2)-Bagging seal ing(300*220mmVacuumbags)-sterilization(ultraviolet radiation sterilization)-storage(4? re frigerator,avoid light);(2) The mushroom:fresh mushroom-choosing-take the edible part-washed clean-split-heat pump drying(40?, mushroom 14 h, cutting mushrooms 10 h, drying quantity is2 kg/m2)-Bagging sealing(300*220mmVacuumbags)-sterilization(ultraviolet radiation steril ization)-storage(4? refrigerator,avoid light);(3) The konjak: fresh konjak- slice up(5 mm)- color-protecting(0.2 g/L ascorbic acid)-remove the surface water-heat pump drying(50?, 9h,drying quantity is2 kg/m2)-Bagging sealing(300*220mmVacuumbags)-sterilization(ultraviolet radiation sterilization)-storage(4? refrigerator,avoid light);(4) The yam: fresh yam- cleaning- slice up(5 mm)- to- remove the surface water-heat pump drying(55?, 6h, drying quantity is 1.5 kg/m2)-Bagging sealing(300*220mm Vacuumbags)-sterilization(ultraviolet radiation sterilization)-storage(4? refrigerato r,avoid light);(5) The apple: fresh apple- cleaning- remove the skin of nuclear- slice up(5mm), color protecting(1 g / 100 ml of Nacl solution)- remove the surface water-hea t pump drying(55?, 4h, drying quantity is 1.5 kg/m2)-Bagging sealing(300*220mm Va cuumbags)-sterilization(ultraviolet radiation sterilization)-storage(4? refrigerator,avoid lig ht);(6) The pineapple: fresh pineapple-remove the peel-slice up(6 mm)- heat pump d rying(45?,30 h, drying quantity is 4 kg/m2)-Bagging sealing(300*220mmVacuumbags)-sterilization(ultraviolet radiation sterilization)-storage(4? refrigerator,avoid light);Second, take 6 kinds of fruits and vegetables in the fresh state, after the heat pu mp drying process, and the other under the condition of several drying methods after processing, for each state of fruit and vegetable quality analysis and comparison, and sensory test respectively. The results showed that the heat pump drying process of fru it and vegetable quality is very close tofresh fruits and vegetables, sensory test score i s higher, and longer shelf life relative to other ways; therefore, heat pump drying tech nology in the production of dried fruit and vegetable products have good market pros pects.